What Is the Status Information Telling Me?

In some predefined 'Work breakdown' and 'Report' views and in the 'Plan' inspector, Merlin shows Status information. The status is presented in form of traffic light-colored shapes which are abstract but easily identifiable even to those with vision problems:

Black = check mark
Red = square
Yellow = triangle
Green = circle
No colour = empty circle

The activity status can not be assigned manually, as it is a calculated value. These are its possible states:

Black: Activity is complete
Red: Activity behind schedule (>10%)
Yellow: Activity slightly behind schedule (=<10%)
Green: Activity on time
No colour: Future or unscheduled activity, activity pending